Can I Plug DVD, TV and electric fan all at once in AVR?

I advice that you contact a competent electrician near your neighbourhood to give you the necessary support. I am not an electrician so I can not advice you on the step to take. But whatever step you take, make sure you abide by safety rules. Make sure you do not come in contact with naked electric wires. Make sure you understand the appliances you are pluging so that you do not get it damaged. Best of luck!

Go back to where you bought yor AVR or study the user's manual/leaflet/packaging. They amount of load (watts) they draw is given their. Each individial appliance also requires power and you'd have to add these up and see how many you can plug in at any one time. In case of doubt, list out all your appliances inclusive individual wattage) take to your electronics store and explain your case. They will surely point you the right (and safe) direction. Be warned that overload can damage your equipment/appliance unless protected by fuses.